In the previous post's image, the original 2 strands made by pulling apart 1 double-stranded DNA now each get its compliment made, making each single strand a double strand! So, when we repeat the process in cycle #2, each of the 2 double-stranded DNA copies gets pulled apart to serve as 4 single-stranded DNA templates. This means at the end of the copying cycle, we'll now have 4 double stranded DNA copies that will again be pulled apart to serve as 8 single-stranded DNA templates. And so forth and so on.
In this representation of DNA replication, I'm no longer using simple lines nor the double helical structures to represent the DNA. Instead, I'm using a rounded-cornered square to represent each base pair that is chained to the next base pair. In step 1 the base-pair blue chain is pulled apart from its (complimentary) orange chain, and becomes the template for a new complimentary copy to be made to each chain.
As you see, the color coding is consistent with the images from the previous posts to hopefully make it easier to follow along as I apply the same principle to this version. You'll see that once the primers in step 2 are stuck to the single-stranded DNA template, new base pairs complimentary to the template are added to the chain with the help of the enzyme (purple hand-like blob) Taq. Finally, in step 5 the 2 new double-stranded DNA copies are now themselves pulled apart, just as they were in cycle #2 of the previous post, to now serve as 4 separate single-stranded DNA templates with which to make 4 new double-stranded DNA copies!
As you see, the color coding is consistent with the images from the previous posts to hopefully make it easier to follow along as I apply the same principle to this version. You'll see that once the primers in step 2 are stuck to the single-stranded DNA template, new base pairs complimentary to the template are added to the chain with the help of the enzyme (purple hand-like blob) Taq. Finally, in step 5 the 2 new double-stranded DNA copies are now themselves pulled apart, just as they were in cycle #2 of the previous post, to now serve as 4 separate single-stranded DNA templates with which to make 4 new double-stranded DNA copies!
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